Serious Question

[fordluvr]

I have a great 1991 Ranger XLT P/U 4.0 that has 185K miles and never had a problem until now. There isn't a set pattern but it is now cutting out when accelerating or pulling up a hill. The other day it cut off while driving and wouldn't restart until it sat for about 1 hour. I replaced plugs, wires, fuel, and air filter and a shop replaced the fuel pump. Same problems exist. The shop has no idea what is wrong...no computer codes show up. Help!

 

[TedJ]

When it won't restart, check for spark/fuel pressure.

If there's no spark, check coil pack and ignition module (probably up in front of battery) and possibly the crankshaft position sensor

If no fuel, check the fuel pressure regulator (could cause stumbling uphill, but idk about a no-start condition), or the fuel pump relay (pump was already replaced).


I'd bet on more of an ignition problem as it seems more likely to be causing the symptoms you described... but finding out what works and what doesn't when it's broken gives a general place to start troubleshooting. Throwing parts at a problem usually leaves a nice hole in your wallet and nothing left to replace that last $.05 part thats the problem. I wouldn't go back to that shop IMO.

-Ted

 

[Mud Bug 94]

fuel pressure regulator.